Simultaneous inoculation with beneficial and pathogenic microorganisms modifies peanut plant responses triggered by each microorganism

FIGUEREDO, MARÍA SOLEDAD; IBÁÑEZ, FERNANDO; RODRÍGUEZ, JOHAN; FABRA, ADRIANA

PLANT AND SOIL

SPRINGER

Año: 2018

0032-079X

Background and aims Plant signaling pathways activatedby single microbial species may be modified by thepresence of other microbial groups. Here, link betweenphenotypic changes of peanut plants co- inoculated withBradyrhizobium sp. SEMIA6144, Bacillus sp. CHEP5and Sclerotium rolfsii, and molecules involved in peanutresponses to each microorganism was evaluated.Methods Phenolic compounds content, peroxidase activityand AhSymRK gene expression were evaluated inplants co-inoculated and inoculated with eachmicroorganism.Results Peroxidase activity, associated with peanut responseto the pathogen, was induced earlier in plants coinoculatedthan in those inoculated only with S. rolfsii, incoincidence with their more tolerant phenotype to thispathogen. The increase in phenolic compounds contentinduced by the biocontrol agent Bacillus sp. CHEP5 wasaffected by the co-inoculation with Bradyrhizobium sp.SEMIA6144. However, the bacterial protection againstS. rolfsii remains unaltered. In co-inoculated plants,AhSymRK gene expression level was similar to plantsinoculated only with the microsymbiont, in concordancewith their symbiotic phenotypes.Conclusions We demonstrated that responses triggeredin peanut plants by single microbial species populationsare modified in presence of others, highlighting therelevance to improve our understanding about plantresponses to soil microbial communities.